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If we're going to have a diary, we have to be able to add entries to it. Let's use sys.stdin so we can capture new lines and tabs and all sorts of other goodies.
New terms
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sys- a Python module that contains functionality for interacting with the system -
sys.stdin- a Python object that represents the standard input stream. In most cases, this will be the keyboard
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[MUSIC]
0:00
Well, we have a table and a menu for
actions.
0:04
Let's write the function that'll actually
let us add entries to the database.
0:07
Python comes with a library named SYS that
relates to system functionality on
0:10
your computer.
0:14
We're gonna use a great feature of that
library, STDIN, so
0:15
that we can capture an entry that has new
lines in it.
0:18
Since we're going to be using the sys
library, we should probably go ahead and
0:21
import it.
0:25
[BLANK_AUDIO]
0:26
Not that it's really important, but
0:28
I'd like to point out that we have the
stuff that comes from Python here, and
0:30
then a blank line, and then the stuff that
comes from a third-party library.
0:33
This is a really good and really common
way of organizing your imports.
0:38
I suggest that you kinda stick to it.
0:41
Okay.
0:44
Let's come down here and check out our Add
Entry function.
0:45
Cuz this is where we're gonna use sys.
0:48
So, it's gonna capture everything that the
user types,
0:51
until they enter what's known as an End of
File key sequence, an EOF key sequence.
0:54
The way that you get this End of File is
by pressing CTRL and D at the same time.
0:59
So, let's tell the users that.
1:05
So print, Enter your entry, press CTRL D
when finished.
1:08
Kay.
1:17
Now, we need to actually capture their
input.
1:19
And this is where the STDIN that I talked
about comes into play.
1:22
So let's call this data,
1:26
and it's gonna be sys.stdin, which is just
like the keyboard.
1:28
And then read, bringing in all the data,
1:32
everything that comes in from here, and
then, oops, and then strip.
1:35
Get rid of any of the white space on
either side of that.
1:39
Now though, we need to make sure that we
actually got something from them.
1:42
So let's say if data.
1:50
So cool, we've got data.
1:53
Something actually came in.
1:54
And then, let's make sure that they want
to save this.
1:56
So if input save entry?
1:59
And we're gonna have a Y and an N, and
then we're gonna lowercase that.
2:04
So if that comes in, and it doesn't equal
n, input comes in,
2:10
they answer with anything other than n
upper case or lower case doesn't matter,
2:16
but anything other than the letter n
[LAUGH], then we wanna do something.
2:21
And what we wanna do is we wanna call
entry.create cuz we're creating a new
2:25
entry, right?
2:29
Did you forget about the model?
2:30
I almost did.
2:32
And we're gonna say the content of our
entry is the data that they just typed.
2:33
And then let's print out saved
successfully.
2:39
And that's it.
2:44
We don't have to do anything else.
2:46
Well we do have to add another blank line
there.
2:49
So we're creating an instance for printing
out a message.
2:52
I'm pretty sure that covers all the stuff
we have to do on adding an entry.
2:55
So let's try it.
2:59
Come right down here ./diary.
3:03
Oh, I love that.
3:04
So much better.
3:06
All right, and let's say A for add an
entry.
3:07
And I'm gonna my entry.
3:10
So I'm gonna say working with databases
has been really neat.
3:12
I'm glad I can show this off.
3:21
I can even have multiple lines.
3:28
Okay.
3:31
And then I hit CTRL and D.
3:32
It comes back with save entry.
3:35
So I'm gonna say yes.
3:37
Actually I can just press Enter.
3:40
And it came back with Saved Successfully.
3:42
That's great.
3:44
Let's try doing one where I don't wanna
save it.
3:46
I don't want to save this entry.
3:48
Ctrl+D, no don't save that.
3:51
It just goes straight back.
3:54
I didn't save anything.
3:56
It just takes me straight back to the
menu.
3:56
I think this is actually working really,
really well.
3:58
Now that we can add things, we need to be
able to see them.
4:00
Let's tackle that in the next video.
4:03
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